May 8, 1998
For Immediate Release
Deborah Pettibone (716) 845-8593
EMBARGOED UNTIL 6 P.M., MAY 8, 1998
INHALED CELLULOSIC AND PLASTIC FIBERS FOUND IN HUMAN LUNG TISSUE
BUFFALO, NY - John L. Pauly, PhD, and colleagues in the Department of
Immunology and the Division of Pathology at Roswell Park Cancer Institute
(RPCI), have published the first report of the discovery of inhaled
cellulosic and plastic fibers in human lung tissue. The fibers observed in
the human lung may be bioresistant and biopersistent candidate agents
contributing to the risk of lung cancer. The results are published in the
May, 1998 issue of Cancer Epidemiology, Biomarkers & Prevention.
The objective of the study was to determine if inhaled plant (i.e.,
cellulosic, e.g., cotton) and plastic (e.g., polyester) fibers are present
in human lung tissue and, if so, whether inhaled fibers are also present in
human lung cancers. "Because airborne fibers are recognized to be
ubiquitous, we hypothesized that some of these fibers might be inhaled,"
according to Dr. Pauly. "Further, we theorized that some of these fibers
might escape the mucociliary mechanisms of the lung, particularly fibers
inhaled by habitual smokers and those whose clearance mechanisms have been
impaired."
To find the answers, the researchers obtained specimens of lung
cancer of different histologic types and adjacent nonneoplastic lung tissue
from patients undergoing lung surgery to remove a tumor. Using laboratory
safeguards to prevent contamination, the specimens were compressed between
two glass microscope slides and viewed by white light, fluorescent light,
polarizing light and contrast illumination. Pilot experiments were then
conducted with these procedures for viewing lung tissues for inhaled
fibers. Near-term fetal bovine lungs and non-lung human tumors were used as
controls.
Due to opposing light refraction characteristics between all fibers
(except glass) and lung tissue, the researchers focused their attention on
viewing fresh human lung tissue samples with a polarizing microscope. "In
one study of 114 human lung specimens (81 nonneoplastic and 33 malignant
tissues) we were able to document the discovery of inhaled cellulosic
and/or plastic fibers in 99 (87%) of the cases," according to Pauly. Of these 99
cases, 67 (83%) were nonneoplastic lung specimens and 32 (97%) were
malignant lung specimens.
The inhaled fibers discovered were heterogeneous (e.g., type,
color, shape, length, diameter, optical properties and other
characteristics). Significantly, notes Pauly, "Most fibers exhibited little
or no deterioration, supporting our premise that inhaled cellulosic and
plastic fibers were bioresistant and biopersistent."
While the research team makes no claim that these observed inhaled
fibers are causative agents or confounders in lung pathogenesis, they are
confident that the results of this study might be the impetus for
additional studies which will provide insights into the complex and diverse
mechanisms underlying malignant transformation.
Dr. Pauly points out that more people die worldwide of lung cancer
than of any other disease and the incidence of lung cancer among smokers
and non smokers is increasing. "The high mortality of lung cancer not
associated with smoking has renewed interest in the risk assessment of
occupational and environmental settings."
Roswell Park Cancer Institute was founded in 1898, is the nation's
first and one of its largest cancer research, treatment and education
centers and is the only National Cancer Institute-designated comprehensive
cancer center in Western New York.
-30-
RSS